## Answers

**Answer:**

Number of customers | Number of days average was observed | Probability | Cumulative Probability |

40 | 10 | 0.05 | 0.05 |

55 | 16 | 0.08 | 0.13 |

85 | 30 | 0.15 | 0.28 |

125 | 24 | 0.12 | 0.40 |

145 | 50 | 0.25 | 0.65 |

175 | 40 | 0.20 | 0.85 |

200 | 20 | 0.10 | 0.95 |

245 | 10 | 0.05 | 1.00 |

Option 1)

No of Kiosks required to meet the demand 95% of the time = **8 Kiosks**

Option 2)

**No of Kiosks required to meet 125% of average demand + 15% of growth =** **8 Kiosks**

Are there any other issues that need to be considered?

**Yes. Another important thing that needs to be considered is the waiting time of customers.** As a customer arrives and get served at a kiosk, some other customers will wait in the queue. If the queue becomes long, the waiting will increase which will affect the customer satisfaction for the service. **Another important factor that will be required to consider is how many customers can be accomodated in the queue. Because a larger queue will require larger space for customers**.

Otherwise, there will be congestion during peak hours and customers will be further dissatisfied if there is not enough space for waiting in queue for a Kiosk.

**CALCULATIONS:**

Number of customers | Number of days average was observed | Probability | Cumulative Probability |

40 | 10 | =10/200 = 0.05 | 0.05 |

55 | 16 | =16/200 =0.08 | = 0.05 + 0.08 =0.13 |

85 | 30 | =30/200 =0.15 | =0.13+0.15 =0.28 |

125 | 24 | =24/200 =0.12 | =0.28+0.12 =0.40 |

145 | 50 | =50/200 =0.25 | =0.40 +0.25 = 0.65 |

175 | 40 | =40/200 =0.20 | =0.65 + 0.20 =0.85 |

200 | 20 | =20/200 =0.10 | =0.85 + 0.10 =0.95 |

245 | 10 | =10/200 =0.05 | =0.95 + 0.05 =1.00 |

**First case**

From above table, 95% of the time, demand is less than or equal to 200 customers per hour.

So, to meet the the estimated peak hourly demand 95% of the time, the kiosks should be able to serve st least 200 customers.

Therefore,

No of Kiosks required to meet the demand 95% of the time = 200/25 = **8 Kiosks**

**Second case**

Estimated average demand

= 0.05*40 + 0.08*55 + 0.15*85 + 0.12*125 + 0.25*145 + 0.20*175 + 0.10*200 + 0.05*245

=**137.65 customers per hour**

For second option, 125% of average demand = 1.25*137.65 =172.1

Growth allowance = 0.15*172.1 = 25.89

Total demand = 172.1 + 25.89 = 198 customers per hour

**No of Kiosks required =** 198/25 = **7.92 8 kiosks**